Multiple-compartment containers are generally known in the art. Such containers may be used for many purposes, for example sequentially delivering two cooperating compositions or to deliver an aesthetic effect, and in other cases the container may be used to separate two reactive components of the composition. Dual compartment containers have been described in many forms and using a number of different dispensing mechanisms. EP 479 451 and WO97/31095 both describe multiple-compartment containers dispensed using a spray device, wherein a feed line from each compartment is linked to the spray nozzle and the compositions for each compartment are then dispensed using a manually or electrically operated pump system. U.S. Pat. No. 5,765,725 also describes a container, employing a different means of dispensing using a pump system. In this case the compositions are dispensed by squeezing the container. However, not every composition is suitable for spraying or even pumping especially where for example ingredients may be sensitive to the pressures of spraying or pumping, or the composition may be prone to undesirable foaming or alternatively the compositions may simply be too viscose to spray or pump. Moreover such spray or pump designed containers can be expensive to make and are not suitable for storing or dispensing large quantities of flowable product.
Compositions can also be dispensed using gravity in dual compartment pouring containers. Examples of such containers include those described in U.S. Pat. No. 4,678,103, U.S. Pat. No. 4,958,749 and U.S. Pat. No. 4,585,150. The containers described in these documents are pouring bottles. However such bottles present a number of problems that the Applicant has sought to solve. For example such bottles require the user to lift and tip at a specific angle in order to achieve the correct ratio of the first to the second compositions dispensed. Moreover the bottles described in these documents involve complicated designs of bottles inside bottles in order to achieve a constant dispensing ratio. Such complicated designs are difficult and expensive to make on a large scale.
Detergent compositions general require a number of active components, some of which can be chemically aggressive, whilst others are chemically sensitive. For this reason, especially when the compositions comprising such components are flowable products, it can be desirable to separate aggressive from sensitive components. Examples of aggressive components include especially oxidising agents, e.g. bleach, whilst sensitive ingredients may include oxidisable agents for example, enzymes, colouring agents and fragrances. Another problem identified when using the multiple-compartment packages available on the market is cross contamination of the compositions in the first and second compartments. Clearly cross contamination is a serious problem if the rational for using a dual compartment bottle is to keep specific ingredients separate. Nevertheless it has been found that containers designed according to U.S. Pat. No. 4,678,103 and U.S. Pat. No. 4,585,150 result in significant cross contamination during and especially at the end of pouring. Another problem is the safety of the container, for example where an aggressive ingredient is stored in the first compartment and more sensitive ingredients, in the second compartment. It has been found possible for the user to dispense from one compartment only, thus using a compositions which is potentially overly aggressive, which may result in damage to the surface to which the composition is applied e.g. fabrics or porcelain, and may even result in irritation of the skin of the user. Alternatively the user may dispense only the composition comprising the more sensitive components, resulting in the use of a composition which does not meet their requirements. Examples of containers where such is possible are described in U.S. Pat. No. 5,692,626 and WO94/16969.
In response to these problems of prior art multiple-compartment containers, the Applicants have developed a multiple-compartment container comprising a first and a second compartment, but optionally further compartments, that is capable of dispensing flowable products by gravity, preferably at a constant volume ratio and which also combats all of the above discussed problems.